Dear All: I am trying to run a system of over 30 atoms.Is it possible to do it with AKAIKKR?

It seems not work by just changing some of the parameters in "specx.f".

Thank you!

237

Re:how to run a system of over 30 atoms?

Posted on : April 13, 2007 (Fri) 12:35:51

by H. Akai

It is still possible to run for a system with over 30 atoms.Take care about the following:

1) Decrease the number of k-points in order that the memoryaddressing does not overflow (in the case of 32bit addressingsystem, such as Pentium 4 with 32bit addressing). This can bedone by decreasing "nk1x". The test run should be donebu "bzqlty=0" or "bzqlty=1" for which nk1x=1~20 wouldbe enough.

2) Increase the number aoms that can be handled:For that increase "natmmx", "ncmpmx", and "msizmx".

For example if you have 30 atoms and for each atom you would like to calculate up to d states (l=2),all atoms have different types, each site has a single component(i.e. not a random alloy) the following parameters are suitable:natmmx=30, ncmpmx=30, msizmx=270, mxlmx=3

238

Re^2:how to run a system of over 30 atoms?

Posted on : April 14, 2007 (Sat) 10:27:57

by zhoul

Thank you for your patient guide.

Now I have successfully set the parameters as the following cases: natmmx=32, ncmpmx=5, msizmx=300, mxlmx=3,nk1x=20,nk3x=21

Besides,it still could be done when I decresed the number of atoms to about 6.

>It is still possible to run for a system with over 30 atoms.>Take care about the following:>>1) Decrease the number of k-points in order that the memory>addressing does not overflow (in the case of 32bit addressing>system, such as Pentium 4 with 32bit addressing). This can be>done by decreasing "nk1x". The test run should be done>bu "bzqlty=0" or "bzqlty=1" for which nk1x=1~20 would>be enough.>>2) Increase the number aoms that can be handled:>For that increase "natmmx", "ncmpmx", and "msizmx".>>For example if you have 30 atoms and for each atom >you would like to calculate up to d states (l=2),>all atoms have different types, each site has a single component>(i.e. not a random alloy) the following parameters are suitable:>natmmx=30, ncmpmx=30, msizmx=270, mxlmx=3